If you can't hear audio on your phone, first check the volume, silent mode, and Do Not Disturb settings.
Next, open a different site on your browser in the same tab you are using for the site with no audio such as a news site or similar site and confirm that you can hear audio from a different site.
If there is no audio from any site, these are the most common issues/reasons for no sound from a browser on a phone:
You phone has multiple volume levels for ringing, media, notifications and similar levels. The media volume is muted or low;
The audio on the video player window is muted, confirm that the speaker icon in the video player window does not have a diagonal line through it. Click the speaker to remove the line;
The browser or the browser tab is muted, confirm that the browser is not muted;
The audio is going to a Bluetooth device. Disconnect from all Bluetooth audio devices;
Ensure your phone's volume isn't muted or set to a low level;
For Chrome: Open Chrome, tap the three-dot icon, select Settings, then Site settings, and choose Sound. Enable the toggle for sound and remove any muted websites.
Other Browsers: Look for similar sound settings or permissions in your browser's settings.
Clear your browser's cache and cookies, as they can sometimes cause audio issues and be sure your browser app is updated.
If there is audio from another site while playing video in the same browser tab and no audio from our site, the video window is muted. Locate the speaker icon in the middle lower area of the video window click the speaker icon until the diagonal line is removed.